﻿<p>The <em>IfcSizeSelect</em> provides for the selection between different measure types used for provision of a length measure.</p>

<blockquote class="note">
NOTE&nbsp; global units are defined at the single <em>IfcProject</em> instance, given by <em>UnitsInContext:IfcUnitAssignment</em>, the same units are used for the geometric representation items and for the style definitions.
</blockquote>

<blockquote class="extDef">
NOTE&nbsp; Definition according to ISO/CD 10303-46:1992<br>
The size select is a selection of a specific positive length measure.</blockquote>

<blockquote class="note">
NOTE&nbsp; Type adapted from <strong>size_select</strong> defined in ISO10303-46.
</blockquote>

<blockquote class="history">
HISTORY&nbsp; New select type in IFC2x2.
</blockquote>

<blockquote class="change-ifc2x3">
IFC2x3 CHANGE&nbsp; The SELECT item <em>IfcMeasureWithUnit</em> has been removed from the <em>IfcSizeSelect</em>, the <em>IfcRatioMeasure</em> and <em>IfcDescriptiveMeasure</em> have been added.
</blockquote>